255/40/18 Rears.....Cheap Internet price!
- Thread starter shiney28
- Start date
Wooooaaahhhhh. Things that appear to be bargains are generally cheap for a reason. :!:
I certainly don't consider myself the font of all knowledge but I'd sugggest that this situation is no different.
The Tyre Load rating on those tyres is 99 which is VERY high. Probably way higher than what you want on the tail end of a Z. The sidewalls are going to be too stiff for the car. In actual fact they're going to be too stiff for most cars - hence they're so cheap.
In load rating terms, I have 92 on the front and 94 on the rear of my 330i Touring. Both are rated "Extra Load". In Kg terms, the ratings are 630Kg and 670Kg respectively. 99 equates to 775Kg! (For reference, a Porsche Spec 235 section front tyre is rated only at 545Kg).
I don't know what I had on my Cerbera because it's now gone (where's the 'crying' smilie?) but at least the upside is that that was always step 1 of my Z4MC path...
I certainly don't consider myself the font of all knowledge but I'd sugggest that this situation is no different.
The Tyre Load rating on those tyres is 99 which is VERY high. Probably way higher than what you want on the tail end of a Z. The sidewalls are going to be too stiff for the car. In actual fact they're going to be too stiff for most cars - hence they're so cheap.
In load rating terms, I have 92 on the front and 94 on the rear of my 330i Touring. Both are rated "Extra Load". In Kg terms, the ratings are 630Kg and 670Kg respectively. 99 equates to 775Kg! (For reference, a Porsche Spec 235 section front tyre is rated only at 545Kg).
I don't know what I had on my Cerbera because it's now gone (where's the 'crying' smilie?) but at least the upside is that that was always step 1 of my Z4MC path...
?
Need to go and check my new ones now....
DaveR said:
It might transmit a bit more vibration into the car, but as long as you don't go below the original load rating there's nothing wrong with going up a bit.
The standard Conti SportContact M3 in 255/40r18 has a 95 load rating which equates to 690kg - so these others will be about 10% higher. However, the load rating is not the actual load it can carry, but a function of how much load the tyre can carry at it's rated maximum speed - and it also specifies an inflation pressure to meet that index. If you increase or decrease the pressure, the load index goes up or down respectively - so a 99 index tyre with 30psi in it would have the same load capacity as a 95 index tyre with 35psi in it.
In fact, my e34 M5 which weighed between 1600 and 1800kg (depending on which of the two I'm talking about, and how it was loaded) had 95 index all round - and the Z4 is 100-300kg lighter.
The price of the 99 rated tyre on other tyre websites is around £200, so they're not discounting it due to the extra load factor as plenty of cars will need that extra load as a minimum.
mmm-chap, I don't doubt that you know more about this than me! :drinkwine:
Looking at the high number of other 99 rated tyres in 255/40 options on mytyres.co.uk for example, it seems very common and I think I need to eat some of my previous words. Apols to all.
The reason for the tyrefit direct discount on the SC2 is probably that they want to get rid of their remaining stock and sell the SC3 (also 99 rated) at £216 instead - in which case the SC2s probably are a genuine bargain.
Without wishing to dig myself a whole new hole, I guess it's fair to suggest that BMW would originally have specced spring rates and dampers to work in conjunction with a given amount of tyre wall flex (related to Load Index?). Whatever that was, since there seems to be general agreement that replacing the OEM springs with Eibach ones yields a ride improvement, I guess it doesn't matter to anyone who has done or is planning on doing that as, if you change one variable, the whole original equation goes out of the window!
I've no recent Conti experience but of those I have tried, BMW or Cerbera, my votes are:
Goodyear F1 GS-D3 - very good.
Dunlop 9000 - disastrous
Goodyear F1 Assymetrico - superb
Michelin PS3 - superb
Looking at the high number of other 99 rated tyres in 255/40 options on mytyres.co.uk for example, it seems very common and I think I need to eat some of my previous words. Apols to all.
The reason for the tyrefit direct discount on the SC2 is probably that they want to get rid of their remaining stock and sell the SC3 (also 99 rated) at £216 instead - in which case the SC2s probably are a genuine bargain.
Without wishing to dig myself a whole new hole, I guess it's fair to suggest that BMW would originally have specced spring rates and dampers to work in conjunction with a given amount of tyre wall flex (related to Load Index?). Whatever that was, since there seems to be general agreement that replacing the OEM springs with Eibach ones yields a ride improvement, I guess it doesn't matter to anyone who has done or is planning on doing that as, if you change one variable, the whole original equation goes out of the window!
I've no recent Conti experience but of those I have tried, BMW or Cerbera, my votes are:
Goodyear F1 GS-D3 - very good.
Dunlop 9000 - disastrous
Goodyear F1 Assymetrico - superb
Michelin PS3 - superb
It may simple be a case of him trying to get rid, or a data entry error, or they could be very close to their age limit for selling.
The SportContact 2 has been around quite a while, and the SportContact3 started replacing the range about 2 years ago - and I've even seen SportContact5 listed (don't know what happened to 4).
I've also seen some AutoBild magazine testing at the 'Ring with new Continental ForceContact tyres - which look like they'll be a rival to the Pirelli Corsa and Michelin Cup range.
The SportContact 2 has been around quite a while, and the SportContact3 started replacing the range about 2 years ago - and I've even seen SportContact5 listed (don't know what happened to 4).
I've also seen some AutoBild magazine testing at the 'Ring with new Continental ForceContact tyres - which look like they'll be a rival to the Pirelli Corsa and Michelin Cup range.
Anyone seen deals like this recently?
Left a post about Costco in the deals section for Michilin PS3's for a complete set of 4 for £469 fitted, but the 20% off deal ended yesterday. Post about old Tyres is so true & a real false economy on a motor that is capable of handing out some abuse.
Was running a set of BF Goordich NRf's and the Michilins feel really settled on the car, no road noise & with only a tad of tramlining. Hear some go on about the Michilin PS2 being better, though you'll highly likely to only get real benefit on a track at the limit IF you know how to properly balance & equally settle the pressures on yr tires through the warmups & practise.
For me, My baby Growler's too special to play too hard on the roads, can't believe what a police car magnet it is since owning it,damn things appear from nowhere so PS3 will be just fine for me.
Best of luck with yr tyre hunt & if Costco have another one of their deals in the future & you're in Kent, happy to let a member get use of my card to get that discount.
J
J
Was running a set of BF Goordich NRf's and the Michilins feel really settled on the car, no road noise & with only a tad of tramlining. Hear some go on about the Michilin PS2 being better, though you'll highly likely to only get real benefit on a track at the limit IF you know how to properly balance & equally settle the pressures on yr tires through the warmups & practise.
For me, My baby Growler's too special to play too hard on the roads, can't believe what a police car magnet it is since owning it,damn things appear from nowhere so PS3 will be just fine for me.
Best of luck with yr tyre hunt & if Costco have another one of their deals in the future & you're in Kent, happy to let a member get use of my card to get that discount.
J
J
I'm having a bit of a mare sourcing and choosing tyres.
Really want to stick with Contis but can't find a set of rears (CCS 5)
I believe I have a puncture, a slow one and would rather get it sorted but not keen on OEM m3 as it's old tech,
Also why are 255\35 r18 showing up as Z4M fit?
Cheers for any info
T1b
Really want to stick with Contis but can't find a set of rears (CCS 5)
I believe I have a puncture, a slow one and would rather get it sorted but not keen on OEM m3 as it's old tech,
Also why are 255\35 r18 showing up as Z4M fit?
Cheers for any info
T1b
AFAIK, then Conitnental SC5 is not available in the ///M's rear size yet, nor is the Michelin PSS.T1berious said:
The best Conti you'll get for the rears at the moment is the SportContact 3 - but IIRC they're only available in an XL rating.
However, if you've got a puncture and are not able/willing to repair it, then you'll have to replace both tyres on that axle if you're going to change to a different type of tyre - after all you wouldn't want 10 year old tech on one side and cutting-edge tech on the other.
I normally don't put my model/reg into search engines for tyres, so don't know what is throwing up that size as a Z4M tyre. But, there's nothing stopping you fitting a 255/35, 265/35 or 265/40 tyre to the rear of a Z4M - it's just that the 255/40 is the recommended/OEM size.T1berious said:
